Expansion module

Information

  • Patent Grant
  • 6498729
  • Patent Number
    6,498,729
  • Date Filed
    Thursday, February 15, 2001
    24 years ago
  • Date Issued
    Tuesday, December 24, 2002
    22 years ago
Abstract
A computing device with an expansion module that may be removed and replaced in an expansion slot is disclosed. The computing device includes computer circuitry to which the expansion module may be electrically connected by means of electrical connectors. The expansion module is coupled to a removable portion of the housing so that when said portion is swung open with assistance of mechanical force, the expansion module is simultaneously disengaged from the computer circuitry. Thereafter, the expansion module can be further removed from said portion.
Description




FIELD OF INVENTION




This invention relates to a computing device with an expansion module.




BACKGROUND OF THE INVENTION




It is well known that the performance of a computer may be enhanced by the use of expansion modules. Known expansion modules, or boards, may, for example, increase the memory or improve the sound or video capabilities of a computer. The computer will typically receive and accommodate the expansion module in one or more available expansion slots. However, it is also common, as in the case of memory expansion, for an existing module in an expansion slot to be replaced by an expansion module with improved performance. Memory expansion can include both increasing the size of Random Access Memory (RAM) and upgrading information or program code on Read Only Memory (ROM).




Desktop computers typically have expansion slots located within the main casing of the computer. In general, the computer casing has to be opened up before a new expansion module can be added. Portable computers tend to be less expandable than their desktop counterparts. This is usually due to the limited space available within the computer casing.




A known laptop computer, the OmniBook® 5500CT (available from Hewlett-Packard, USA), includes two memory slots that accommodate two memory expansion boards. To add a new memory board, a user initially removes a cover portion of the housing from the memory expansion slot. If a memory expansion board is already present, then it may be pulled out by the user. The user then positions the new memory board over the two connectors in the slot and presses down on the board until it seats fully.




A drawback with the expansion slot in the OmniBook® computer is that the expansion module is prone to damage. Firstly, the memory board contains memory chips that can be damaged by electrostatic discharge caused by manual handling. Secondly, applying manual pressure directly on the memory board when it is pushed into place can cause the board to crack. The user may not realize that the memory board is seated fully and may further increase pressure on the board in an attempt to position it properly. Thirdly, a user may attempt to position the new memory board in an incorrect orientation in the expansion slot that can result in damage to the connectors and the memory chips.




A known handheld computer, the HP 340LX (available from Hewlett-Packard, USA), uses a ROM chip to store the operating system code. When it is desired to upgrade the operating system, the user simply removes a cover portion from the front of the computer, slides out a circuit board module with the old ROM chip, and replaces it by sliding in a new expansion module with an upgraded ROM chip. Like the OmniBook® expansion module, the expansion module for the HP 340LX is also prone to damage from manual handling during insertion.




A solution to the preceding problems is provided in a pending US patent application entitled “Expansion Module” with the serial number of 09/354,235, assigned to the current assignee. According to this patent application, the expansion module is coupled to a removable portion of the housing so that when the housing portion is replaced, the expansion module is simultaneously received in the expansion slot. The housing portion may then be slid laterally to a locking position. Nonetheless, in this patent application, the user needs to remove the keyboard and unfasten three screws that secure the keyboard located at the bottom of the case in order to get access to the expansion mode. This procedure makes the replacement inconvenient.




Therefore, there exists a need for a more convenient way to realize the replacement of expansion modules without enhancing the risk of damage to the module.




SUMMARY OF THE INVENTION




In a preferred embodiment, the invention provides a computing device with an expansion module that may be removed and replaced by a user with ease and with less risk of damage to the module. The computing device includes computer circuitry to which the expansion module may be electrically connected. Both the computer circuitry and the expansion module include electrical connectors, which when mated provide the electrical connection.




An embodiment of a computing device includes a computer circuitry, an expansion module, and a housing substantially enclosing the computer circuitry. Both the computer circuitry and the expansion module have a respective electrical connector for electrically connecting to each other. The housing has a housing cover that is removable from and replaceable on the reminder of the housing. The housing cover is coupled to the expansion module so that removal of the housing cover simultaneously separates the expansion module from the computer circuit, and replacement of the housing cover connects the two respective electrical connectors. With assistance of mechanical force, the housing cover can be swung open. This action causes the two electrical connectors to separate from each other. Thereafter, the expansion module can be further removed from the housing cover.




Preferably, friction between the two electrical connectors keeps them connected. The mating of the two connectors may further prevent movement of the expansion module. The housing cover is also restricted from movement when the expansion module is secured to the housing cover.




In a preferred embodiment of the invention, the computer device also has a locking means to provide the mechanical assistance for the removal and replacement of the housing cover. The locking means has a rear portion and a front portion, and is removable in a predetermined direction relative to the housing. A part of the housing cover is locked between the two portions. Furthermore, the locking means has a driven means through which the locking means is driven to move in the predetermined direction. When the locking means moves in a removal direction, the rear portion pushes the housing cover so that the housing cover is swung open. This action causes the two electrical connectors to separate from each other, either in partial or complete disengagement. The expansion module can be further detached from the computer circuitry by simply lifting the housing cover up. When the user wants to secure the expansion module, the locking means is driven in a replacement direction opposite to the removal direction. The front portion pushes the housing cover and the housing cover is driven back so that the two electrical connectors are connected and the expansion module is secured. Moreover, the locking means restricts the housing cover from movement when the expansion module is secured.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a schematic cross-section of a computing device in accordance with the invention, with a housing cover and an expansion module in the secured position.





FIG. 2

is a schematic cross-section similar to

FIG. 1

but with the housing cover in an unlocked position and the expansion module partially disengaged from a receptacle.





FIG. 3

is a plan view of the housing cover and a screw head being rotatable in two positions of “lock” and “unlock.”





FIG. 4

is a perspective view of a cam with a screw head and the housing cover having the cam follower's profile incorporated.





FIG. 5

is a perspective view of the housing cover and the expansion module in accordance with the invention.





FIG. 6

is a perspective view of the housing cover and the expansion module of

FIG. 5

in a coupled state.











DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT





FIG. 1

shows a computer


10


with an expansion slot


12


for accommodating an expansion module


30


. The computer


10


may be a handheld portable computer, and the expansion module


30


may be a RAM or ROM module.




The computer


10


has a generally rectangular housing


40


, a mother board


50


, and an expansion module


30


. The housing


40


is made, for example, of a plastics material and encloses the mother board


50


. The mother board


50


is in the form of a standard printed circuit board (PCB) on which a female electrical connector or receptacle


60


is mounted. Other electronic components are also mounted on the mother board


50


, such as, for example, a central processor unit, a video display chip, and an input/output chip. The housing


40


includes a removable housing cover


44


. At one end of the housing cover


44


, the housing cover


44


incorporates two tabs


47


which are tucked under a main body portion


42


of the housing


40


(see FIG.


4


). The other end of the housing cover is movable.




The removable housing cover


44


is coupled to the expansion module


30


such that the expansion module


30


lies adjacent the major underside surface of the housing cover


44


. The expansion module


30


has a male electrical connector or connector plug


32


mounted on a surface which faces away from the housing cover


44


in the coupled state.




As shown in

FIG. 1

, when the housing cover


44


is secured, the connector plug


32


is inserted into the receptacle


60


for electrically connecting the expansion module


30


to the mother board


50


. Thus, replacement of the housing cover


44


simultaneously connects expansion module


30


with the mother board


50


. Similarly, removal of the housing cover simultaneously separates the expansion module


30


from the mother board


50


. As the housing cover


44


is swung open with assistance of mechanical force, the receptacle


60


and the connector plug are separated from each other, and the expansion module


30


can further be detached from the mother board


50


.




In a preferred embodiment, the mechanical force needed to open the housing cover


44


is provided by a cam


20


with a screw head


22


. As shown in

FIG. 3

, the screw head


22


can be rotated between two positions: a “lock” position


24


and an “unlock” position


26


. When the screw head


22


is rotated to the “unlock” position, the housing cover


44


can be detached from the main body portion


42


. For securing the housing cover


44


, the screw head


22


is rotated to the “lock” position.




Typically, the cam


20


has a helical profile, and a cam follower's profile


48


is incorporated in the housing cover


44


. As the cam


20


is being rotated from the “lock” position


24


to the “unlock” position


26


, e.g., by a normal screw driver


70


, the helical profile of the cam


20


pushes the housing cover


44


out. Thereby, the connector plug


32


disengages from its receptacle


60


, either partially or completely (see FIG.


2


). The cam's


20


profile also has an opening


28


(see FIG.


4


). The opening


28


is positioned such that when the screw head


22


is rotated to the “unlock” position, the cam's


20


profile will not block further detachment of the housing cover


44


. The expansion module


30


can be detached from the receptacle


60


by simply lifting the housing cover


44


up with a finger. After the housing cover


44


is fully lifted up, the expansion module


30


can then be replaced or a new expansion module can be coupled to the housing cover


44


.




Likewise, when the expansion module


30


needs to be secured, the cam


20


is rotated from the “unlock” position


26


to the “lock” position. The housing cover


44


is thus pushed back by the cam's


20


profile. This action causes the connector plug


32


of the expansion module


30


to insert into the receptacle


60


. The expansion module


30


is then electrically connected to the mother board


50


, and the replacement of the expansion module is complete. The housing cover


4


is restricted from movement by the cam's profile after the expansion module


30


has been secured. Furthermore, friction between the connector plug


32


and the receptacle


60


keeps them connected. The mating of them also prevents movement of the expansion module


30


.





FIG. 4

illustrates the interaction between the cam


20


and the housing cover


44


. As shown in

FIG. 4

, the cam


20


has a screw head


22


such that the cam can be rotated by a normal screw driver. At one end of the housing cover


44


, the housing cover


44


incorporates two tabs


47


which are tucked under the main body portion


42


of the housing


40


(see FIG.


1


). The other end of the housing cover is movable, where a cam follower's profile


48


is incorporated in the housing cover


44


. Thereby, the housing cover


44


can be pushed out or back by the cam's


20


profile when the cam


20


is rotated. Furthermore, the cam's


20


profile has an opening


28


. When the screw head


22


is rotated to the “unlock” position, the cam's


20


profile will not block the further detachment of the housing cover


44


.





FIG. 5

illustrates the detailed structure of the expansion module


30


and the housing cover


44


as in the preferred embodiment. The housing cover


44


and the expansion module


30


are generally planar and rectangular.




As shown in

FIG. 5

, the housing cover


44


has a pair of front arms


100


located towards the front of the housing cover


44


and a pair of rear arms


110


located towards the rear of the housing cover


44


. All arms depend generally upwards from the upside of the housing cover


44


. The front and rear arms


100


,


110


are located on opposite sides of the housing cover


44


; one front arm and one rear arm are located on the left-hand side of the housing cover, and the other front arm and rear arm are located on the right-hand side of the cover. Each arm in each pair is angled back towards the opposite arm in the pair to define a pair of front longitudinal channels


105


and a pair of rear longitudinal channels


115


.




The expansion module


30


typically comprises a generally rectangular printed circuit board (PCB)


31


on which memory chips


34


and the electrical plug connector


32


are mounted. The dimensions of the PCB


31


are such that the left and right hand sides of the PCB


31


may be accommodated in the corresponding left and right sets of channels in the cover.




To couple the expansion module to the cover, the PCB


31


may be inserted into the pair of rear longitudinal channels


115


and slid forwards until it is received in the pair of front longitudinal channels


105


. Alternatively, however, the housing cover


44


includes a pair of indents


36


on opposite sides of the PCB


31


. These indents allow the PCB


31


to avoid the pair of rear arms


115


, as shown by the dashed lines in FIG.


5


. Thus, the PCB


31


may be slid into the front and rear longitudinal channels


105


,


115


simultaneously.




The front longitudinal channels


105


of the housing cover


44


are blocked at the front end. This blockage prevents the PCB


31


from moving beyond a certain point. With the PCB


31


received at this point, however, the housing cover


44


and expansion module


30


are in a sub-assembly configuration required for insertion into the expansion slot


12


. This sub-assembly configuration is shown in FIG.


6


.




A retaining protrusion


180


is provided in each of the front channels


105


of the housing cover


44


for interacting with a retaining profile or indent


170


on the side of the PCB


31


. In the sub-assembly configuration, each retaining protrusion


180


latches on to the indent


170


to ensure the engagement between the housing cover


44


and the PCB


31


.



Claims
  • 1. A computing device comprising:a computer circuitry having a first electrical connector, an expansion module having a second electrical connector for connecting to the first electrical connector to make an electrical connection to the computer circuitry, a housing substantially enclosing the computer circuitry, the housing having a cover that is removable from and replaceable on the remainder of the housing, said cover being coupled to the expansion module so that removal of the cover separates the expansion module from the computer circuit, and replacement of the cover connects the first and second electrical connectors; wherein the housing is configured such that, mechanically assisted, said cover can be swung open from a locked position in which the expansion module is connected to the computer circuit and direct removal of the expansion module is prevented, to an unlocked position in which the expansion module is at least partly detached from the computer circuitry and may be further removed from the cover, and a locking means for removing and replacing the cover, the locking means being movable in a predetermined direction relative to the housing, having a rear portion and a front portion, wherein a part of the cover is locked between the rear portion and the front portion, the cover thereby being pushed out by the rear portion as the locking means is driven to move in a removal direction, while the cover being pushed back by the front portion as the locking means is driven to move in a replacement direction.
  • 2. The computing device of claim 1, wherein the locking means further comprising a driven means through which the locking means is driven in the predetermined direction relative to the housing.
  • 3. The computing device of claim 1, further comprising a cam with a screw head, wherein the cam is movable in a predetermined direction relative to the housing when the screw head is being rotated, the cover incorporating cam follower's profile at a first end of the cover such that the cover can be driven along with the movement of the cam.
  • 4. The computing device of claim 3, wherein the cam provides the mechanic force for opening the cover.
  • 5. The computing device of claim 3, wherein the cam has a helical profile.
  • 6. The computing device of claim 3, wherein the cover is restricted from movement by the cam's profile when the expansion module has been secured.
Priority Claims (1)
Number Date Country Kind
200001133 Mar 2000 SG
US Referenced Citations (2)
Number Name Date Kind
5337220 Granitz Aug 1994 A
6222726 Cha Apr 2001 B1
Non-Patent Literature Citations (1)
Entry
U.S. patent application Ser. No. 09/354,235, Wong et al., filed Jul. 16, 1999.